Stressful life events during pregnancy negatively affect maternal and infant outcomes including breastfeeding initiation. Their impact on breastfeeding duration is uncertain. Given breastfeeding's important health benefits we analyzed stressful life event types and cessation of any and exclusive breastfeeding by 4 and 13 weeks. Methods. We collected self-administered survey data at 5-7 months postpartum from over 700 primarily urban low-income US mothers. Data covered prepregnancy, prenatal, and postpartum periods including 14 stressful life events (categorized into financial, emotional, partner-associated, traumatic). Analyses included only mothers initiating breastfeeding (n = 341). Logistic regressions controlled for maternal characteristics including a breastfeeding plan. Results. All four stress categories were associated with shorter duration of any and exclusive breastfeeding. In the adjusted models, statistically significant relationships remained for financial stress (4 weeks cessation of any breastfeeding duration) and traumatic stress (13 weeks exclusive breastfeeding cessation). Controlling for stress, a longer breastfeeding plan was significantly associated with a shorter breastfeeding duration (all models) as was depression during pregnancy and current smoking (several models). Conclusions. Among low-income women, impact of stressful life events on cessation of breastfeeding may differ by stress type and interfere with achievement of breastfeeding goal. Among these stressed mothers, breastfeeding may serve as a coping mechanism.